Building regulations have encouraged the development of more energy efficient building construction techniques. Therefore buildings are becoming more air tight via improved draught proofing, double glazing and the use of central heating. The result is an increase in the water vapour content within the building and this combined with better insulated buildings can create a colder loft space and the risk of condensation forming. Condensation, be it surface or interstitial, can damage the roof construction.

People and their normal activities within the building can produce 5-15 litres of water vapour per day. Of this up to 60% can diffuse through gaps in the ceiling, light fittings and loft hatches and enter the roof space.

To counteract this, it has been recommended to ventilate the loft space to allow water vapour to disperse before it can condense and cause damage.

IKO have a range of pitched roofing membranes depending on the type of roof you have.

Breathable (vapour permeable) underlays are for use in ventilated or non-ventilated cold or warm pitched roofs. These are increasingly chosen as they can be used on all roof types.

Alternatively you can use a non breather underlay in ventilated cold pitched roofs.

The IKO pitched roof underlay range is designed to

  • Provide a barrier to minimize the wind uplift load acting on the slates or tiles
  • Provide a secondary barrier to the ingress of wind driven rain, snow and dust
  • Transport any moisture resulting from any ingress through the primary roof covering in to the roof drainage system
  • Provide temporary weather protection before the installation of the primary roof covering.

Click here to learn more about the IKO range.